Some perspectives on fish endocrinology     

Howard A. Bern 《Fish physiology and biochemistry》1989,7(1-6):415-418

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牛生长激素受体基因的研究进展     

蔡锦顺  杜萍 《吉林畜牧兽医》2008,29(6):10-13

生长激素受体基因是家畜生产力的重要候选基因，并成为提高反刍动物奶肉产量等研究的焦点。近年来，有关牛羊生长激素受体基因的研究不断增加，该领域的深入探讨可能产生家畜育种和生产中候选基因研究的突破性进展，而且有助于标记辅助选择的实施。本文主要就牛羊生长激素受体的结构和功能区域的分析，多态性与生产性能的相关研究等方面进行了综述和讨论。  相似文献   

布尔山羊繁殖季节重复超排处理效果研究   总被引：4，自引：1，他引：3  

周占琴  李广  武和平  付明哲  陈小强  潘瑞  郝应昌  刘秀安 《中国农学通报》2003,19(5):1-3

研究共进行了 2个试验。试验Ⅰ ,成年布尔山羊在繁殖季节初期经超排处理 ,平均每只采得有效胚胎 1 7 0 7枚 ,2个月后再行重复超排处理 ,虽有 3只羊未能实现采卵 ,但其它羊只均获成功 ,其中B组 (FSH加量 )平均获有效胚胎 1 5 4 6枚 ,明显高于A组 (FSH未加量 ,平均每只 1 2 93枚 )。试验Ⅱ ,选择了 2 0 0 0年超排效果较好的布尔山羊 ,在 2 0 0 1年和 2 0 0 2年秋季进行了第 2次、第 3次重复超排处理。结果表明 :在生殖器官未发生粘连的情况下 ,第 2次平均获有效胚胎 1 5 83枚 ,与第 1次超排结果 (平均 1 5 5 0枚 )相近。第 3次超排因两只羊生殖器官粘连未能采卵 ,其余 1 0只羊平均采得有效胚胎 1 3 4 0枚。  相似文献   

Sequential preovulatory expression of a gonadotropin-releasing hormone-inducible gene,Nr4a3, and its suppressor Anxa5 in the pituitary gland of female rats     

Ryota TERASHIMA  Titaree LAOHARATCHATATHANIN  Shiro KURUSU  Mitsumori KAWAMINAMI 《The Journal of reproduction and development》2021,67(3):217

Functional relationship between nuclear receptor subfamily 4 group A member 3 (Nr4a3) and annexin A5 (Anxa5), which are two gonadotropin-releasing hormone (GnRH)-inducible genes, has been established while evaluating pituitary gonadotropes in relation to follicle-stimulating hormone beta (Fshb) expression. However, the physiological variations that arise due to the differential expression of these genes in the pituitary gland during rat estrous cycle remain unknown. This study aimed to evaluate the Nr4a3 and Anxa5 mRNA expression during the estrous cycle in rats in comparison with the expression of the gonadotropin subunit genes, luteinizing hormone beta (Lhb) and Fshb. Nr4a3 mRNA expression showed a single peak at 1400 h of proestrus during the 4-d estrous cycle. Anxa5 mRNA level was elevated along with increased Fshb mRNA expression after the decline of Nr4a3 mRNA until 2300 h. Lhb mRNA expression levels were not significantly changed during the estrous cycle. Notably, addition of a GnRH antagonist at 1100 h completely eradicated luteinizing hormone secretion at 1400 h and 1700 h of proestrus, and significantly reduced the Nr4a3 mRNA expression level at both the time points. These results suggest that GnRH is, at least partly, responsible for the increase in pituitary Nr4a3, and that the interaction between NR4A3 and ANXA5 is required to regulate Fshb expression during the preovulatory gonadotropin surge.  相似文献   

Endogenous serum insulin concentration in dogs with diabetic ketoacidosis     

Shannon E. Parsons  DVMKenneth J. Drobatz  DVM  DACVIM  DACVECCStephen V. Lamb  BSCynthia R. Ward  VMD  PhD  DACVIMRebecka S. Hess  DVM  DACVIM 《Journal of Veterinary Emergency and Critical Care》2002,12(3):147-152

Objective: To determine endogenous serum insulin concentration in dogs with diabetic ketoacidosis (DKA), and to compare it to endogenous serum insulin concentration in diabetic dogs with ketonuria but no acidosis (KDM), diabetic dogs with uncomplicated diabetes mellitus (DM) that did not have ketonuria or acidosis, and dogs with non‐pancreatic disease (NP). Design: Prospective study. Setting: Veterinary Hospital of the University of Pennsylvania. Animals: Forty‐four client‐owned dogs; 20 dogs with newly diagnosed diabetes mellitus (7 dogs with DKA, 6 dogs with KDM, and 7 dogs with DM) and 24 dogs with non‐pancreatic disease. Interventions: Blood and urine samples were obtained at the time of admission to the hospital. Measurements and main results: Signalment, clinical signs, physical examination findings, and concurrent disease were recorded for all dogs. Blood glucose concentration, venous blood pH, venous blood HCO3^? concentration, urinalysis, and endogenous serum insulin concentration were determined in all dogs. Dogs with DKA have significantly decreased endogenous serum insulin concentrations compared to dogs with DM (P = 0.03) and dogs with non‐pancreatic disease (P = 0.0002), but not compared to dogs with KDM (P = 0.2). Five of 7 dogs with DKA had detectable endogenous serum insulin concentrations, and 2 of these dogs had endogenous serum insulin concentration within the normal range. Conclusions: Diabetic dogs with ketoacidosis have significantly decreased endogenous serum insulin concentration compared to dogs with uncomplicated diabetes mellitus. However, most dogs with DKA have detectable endogenous serum insulin concentrations, and some dogs with DKA have endogenous serum insulin concentrations within the normal range.  相似文献   

多氯联苯对鸡胚睾丸结构的损伤作用   总被引：5，自引：3，他引：2  

方昌阁  张才乔  夏国良  乔惠理 《中国兽医学报》2002,22(2):168-170

选用海兰鸡作为实验动物 ,研究了多氯联苯 (polychlorinated biphenyl,PCB)对鸡胚胎期性腺发育和生殖细胞分化的影响。在入孵前将多氯联苯商业混合物 Aroclor 12 5 4花生油制剂注入海兰种蛋卵黄内 ,试验 、 、 组剂量分别为 1、10、10 0 μg/枚 ,体积为 10 0 μL,对照组注射等体积花生油 ,统计分析死亡率和孵化率 ,并取出新出壳雏鸡的性腺进行组织学观察。结果表明 ,雄性雏鸡的睾丸结构发生明显改变 ,与对照组相比 ,其横截面积、精细管直径和精细管面积占睾丸横截面积的百分比显著降低。在 组 ,雄性雏鸡的大部分精细管降解甚至消失 ,其睾丸内精细胞的分化受到了不同程度的抑制 ,几乎所有生殖细胞都发生了核固缩和胞质空泡化 ,而在 、 组则只有散在的发生。本试验结果表明 ,PCB干扰鸡胚性腺的发育 ,并具有抑制禽类睾丸发育和精原细胞分化的作用。  相似文献   

雷竹花期激素组成的初步研究     

柴振林  何建荣 《浙江林业科技》2001,21(3):36-37

测定雷竹花期激素组成，从激素角度初步分析了雷竹花开花的原因。  相似文献   

保幼激素类似物对桑蚕消化液蚕白酶的影响     

周乃明  徐俊良 《浙江大学学报(农业与生命科学版)》1990,(2)

采用活体和离体方法研究了保幼激素类似物(JHA)对桑蚕Bombyx mori 消化液蛋白酶的影响。试验结果表明,JHA能显著提高消化液蛋白酶的活性,作用时间在处理后6～24h范围内,随后酶活性逐渐下降至与对照组一致。本文还就激素对中肠消化吸收的调控机制和养蚕生产中JHA使用方法进行了讨论。  相似文献   

锌对雄性动物生殖的影响     

张拴林  黄应祥  岳文斌  张桂贤 《中国牛业科学》2001,27(1):38-40

本文从锌对动物生殖影响的机理、镜在精液及副性腺中的分布、锌对生殖器官及生殖的影响。锌与生殖内分泌的关系。锌与雄性不育等五个方面综述了锌对雄性动物生殖机能的影响，具有一定参考价值。  相似文献   

皮埃蒙特杂种肉牛生长激素基因型与体重、日增重的相关性研究   总被引：1，自引：0，他引：1  

孙少华  李雪梅  魏学蕊  李玉  常泽军 《中国牛业科学》2001,27(4):8-11

本研究利用PCR-RFLPs标记技术，对63头杂种肉牛的生长激素基因的第5外显子和3’端区域进行了分析寿终正寝分现HaeⅢ酶切位点具有多态性，并分为三种基因型（AA、BB和AB）。通过构建最小二乘线性模型。分析了生长激素基因型与杂种肉牛高于12月龄体重和6-12月龄日增重的关系。结果表明：生长激素AB基因型的效应稍高于AA、BB型，但差异不显著。  相似文献